Systemic Biomarkers and Liver Morphology in Rats during Chronic Low-Dose Toxicant Administration against the Background of Vitamin Deficiency

Liver morphology, intensity of apoptosis, and activity of xenobiotic metabolism enzymes were studied in a chronic model experiment in rats receiving a mixture of 6 pesticides against the background of life-long diets with adequate and insufficient supply of water-soluble vitamins. The dose of each pesticide in the mixture did not exceed the acceptable daily intake (1 ADI). It was found that chronic exposure to low doses of anthropogenic toxicants in combination with permanent vitamin deficiency provokes a number of liver changes, such as increased apoptosis activity, cytochrome P450 system depletion, steatosis, and inflammatory infiltration, which is a potential health risk factor.

[Liver gene expression in normal and obese rats received resveratrol and L-carnitine]

The use of nutraceuticals with anti-inflammatory and hypolipidemic activity in the composition of foods for special dietary uses and dietary supplements is one of the effective methods of dietary therapy of alimentary obesity and related diseases. The aim was to study the effect of the combined intake of resveratrol and L-carnitine (RC) on the expression of genes responsible for the metabolism of carbohydrates, fats and inflammatory reactions in the liver and kidneys of rats in normal conditions and with diet-induced obesity. Material and methods. Male Wistar rats received for 63 days a standard balanced diet or a high-fat-high-carbohydrate diet (HFCD) with an excess of total fat (30%) and fructose (20% solution instead of drinking water), or the same diets supplemented with RC in a low (25 mg/kg body weight as resveratrol and 300 mg/kg as L-carnitine) or high (50 and 600 mg/kg body weight, respectively) doses. The expression of genes (Khk, Gck, Pklr, Acaca, Acacb, Fasn, Scd, Srebf1, Mlxipl, Ppara, Pparg, Actb, Gapdh) in liver cells was studied by the method of real-time reverse transcription polymerase chain reaction (RT-PCR). The distribution of tyrosine aminotransferase (TAT), nuclear factor erythroid 2-related factor 2 (NRF-2) and intercellular adhesion molecule type 2 (ICAM-2) in the liver and kidneys was assessed by confocal laser microscopy and immunohistochemistry. Results. Increased expression of Fasn (fatty acid synthase) in rats treated with high-fat high-carbohydrate diet (HFCD) decreased under RC intake. RC consumption caused a decrease in the number of TAT-, NRF-2- and ICAM-2-positive cells in the liver of rats treated with HFCD, but had the opposite effect in the kidneys. The consumption of RC at the low dose by rats fed HFCD caused changes in the expression profiles of the studied marker genes, indicating a possible hypolipidemic effect. However, observed increased expression of lipogenic genes in the liver and elevated level of NRF-2 and ICAM-2 in kidney against the background of consumption of RC with the standard balanced diet cannot be assessed as unambiguously positive. Conclusion. Thus, possible negative effects caused, most likely, by the interaction of nutraceuticals with various mechanisms of action should be taken into account when developing formulations of dietary supplements and foods for special dietary uses for dietary therapy of obesity.

[Influence of the L-carnitine and resveratrol complex on physiological, biochemical and morphological indicators of normal and obese rats]

Specialized products and dietary supplements, enriched with complexes of minor biologically active substances (BAS), are often offered as components of therapeutic diets in the treatment of obesity and metabolic syndrome. At the same time, the possible effects of the interactions of BAS when consuming a multicomponent product have not been studied enough. The aim - to study the action on rats' organism of a complex supplement (RС), containing resveratrol (Res) and L-carnitine (L-Car), when consumed with a standard balanced or hypercaloric diet. Material and methods. Male Wistar rats received for 63 days a standard balanced diet (SD) or a high-fat-high-carbohydrate diet (HFCD) with an excess of total fat (30%) and fructose (20% solution instead of drinking water), or the same diets supplemented with RС in a low (25 mg/kg body weight as Res and 300 mg/kg body weight as L-Car) or high (50 and 600 mg/kg body weight, respectively) doses. The muscle grip strength, behavioral reactions in tests of the conditioned passive avoidance reflex (CPAR) and elevated plus maze (EPM) were studied. At the end of the experiment, the mass of adipose tissue and internal organs was determined together with the activity of microsomal and cytosolic liver enzymes for specific substrates, plasma biochemical parameters, liver morphology by lightoptical microscopy, accumulation of lipofuscin-like granules (LLG) in the liver and kidneys by laser confocal microscopy. Results. In the rats fed HFCD, compared with SD, there was an increase in the mass index of liver, total inguinal and retroperitoneal white adipose tissue, in the levels of glucose and triglycerides, in the activity of hepatic CYP1A1 and CYP3A monooxygenases, UDPglucuronosyltransferase, heme oxygenase, and simultaneous decrease of high and low density lipoprotein cholesterol, and quinone oxidoreductase activity. The RС intake stimulated the locomotor activity of rats in EPM, however, this effect was less pronounced against the background of HFCD consumption. In rats consuming SD (but not HFCD), the addition of RС caused an increase in search activity and anxiety according to the EPM and CPAR data. The effect on short- and long-term memory retention was statistically insignificant. RС intake did not have hypolipidemic and hypoglycemic properties but caused in low dose an increase in the ratio of the activity of transaminases AST/ALT in animals fed HFCD. The liver CYP3A activity increased in rats supplemented with RС in high dose fed HFCD. In the kidneys of animals, the consumption of RС resulted in increased accumulation of LLG. Conclusion. When studying the effect of the complex supplement RС on normal and obese rats according to the studied physiological, morphological and biochemical indexes, no positive effects were revealed, that would not have manifested themselves for Res and L-Car separate intake. No evidence of synergistic action of L-Car and Res were found, and some of the effects of the complex supplement can be considered as adverse. This requires careful assessment when combined using these substances in complex diet therapy of metabolic disorders in humans.

[Full transcriptome analysis of gene expression in liver of mice in a comparative study of quercetin efficiency on two obesity models]

BACKGROUND

Quercetin (Q; 3,3',4',5,7 - pentahydroxyflavone) can help alleviate the pathological effects of nutritional obesity and metabolic syndrome when taken as part of products for special dietary needs and food supplements. The mechanisms of action of Q at the genetic level are not well understood.

AIMS

To study gene expression in liver tissue of mice with alimentary and genetically determined obesity upon intake of Q with diet.

MATERIALS AND METHODS

During 46 days of the experiment on 32 male C57Bl/6J mice fed a diet with an excess of fat and fructose and 24 male genetically obese db/db mice the effect of Q in dose of 25 or 100 mg/kg of body weight was studied on differential expression of 39430 genes in mice livers by full transcriptome profiling on microchip according to the Agilent One-Color Microarray-Based Gene Expression Analysis Low Input Quick Amp Labeling protocol (version 6.8). To identify metabolic pathways (KEGGs) that were targets of Q exposure, transcriptomic data were analyzed using bioinformatics methods in an "R" environment.

RESULTS

Differences were revealed in the nature of Q supplementation action in animals with dietary induced and genetically determined obesity on a number of key metabolic pathways, including the metabolism of lipids and steroids (Saa3, Cidec, Scd1, Apoa4, Acss2, Fabp5, Car3, Acacb, Insig2 genes), amino acids and nitrogen bases (Ngef, Gls2), carbohydrates (G6pdx, Pdk4), regulation of cell growth, apoptosis and proliferation (Btg3, Cgref1, Fst, Nrep Tuba8), neurotransmission (Grin2d, Camk2b), immune system reactions (CD14i, Jchain, Ifi27l2b).

CONCLUSIONS

The data obtained help to explain the ambiguous effectiveness of Q, like other polyphenols, in the dietary treatment of various forms of obesity in humans, as well as to form a set of sensitive biomarkers that allow us to elucidate the effectiveness of minor biologically active food substances in preclinical trials of new means of metabolic correction of obesity and metabolic syndrome.

Comparative Whole-Transcriptome Profiling of Liver Tissue from Wistar Rats Fed with Diets Containing Different Amounts of Fat, Fructose, and Cholesterol

Differential expression of 30,003 genes was studied in the liver of female Wistar rats fed with isocaloric diets with the excess of fat, fructose, or cholesterol, or their combinations for 62 days using the method of whole-transcriptome profiling on a microchip. Relative mRNA expression levels of the Asah2, Crot, Crtc2, Fmo3, GSTA2, LOC1009122026, LOC102551184, NpY, NqO1, Prom1, Retsat, RGD1305464, Tmem104, and Whsc1 genes were also determined by RT-qPCR. All the tested diets affected differently the key metabolic pathways (KEGGs). Significant changes in the expression of steroid metabolism gene were observed in the liver of animals fed with the tested diets (except the high-fat high fructose diet). Both high-fat and high-fructose diets caused a significant decrease in the expression of squalene synthase (FDFT1 gene) responsible for the initial stage of cholesterol synthesis. On the contrary, in animals fed with the high-cholesterol diet (0.5% cholesterol), expression of the FDFT1 gene did not differ from the control group; however, these animals were characterized by changes in the expression of glucose and glycogen synthesis genes, which could lead to the suppression of glycogen synthesis and gluconeogenesis. At the same time, this group demonstrated different liver tissue morphology in comparison with the animals fed with the high-fructose high-fat diet, manifested as the presence of lipid vacuoles of a smaller size in hepatocytes. The high-fructose and high-fructose high-fat diets affected the metabolic pathways associated with intracellular protein catabolism (endocytosis, phagocytosis, proteasomal degradation, protein processing in the endoplasmic reticulum), tight junctions and intercellular contacts, adhesion molecules, and intracellular RNA transport. Rats fed with the high-fructose high-fat or high-cholesterol diets demonstrated consistent changes in the expression of the Crot, Prom1, and RGD1305464 genes, which reflected a coordinated shift in the regulation of lipid and carbohydrate metabolisms.

Effects of Quercetin on Expression of Genes of Carbohydrate and Lipid Metabolism Enzymes in the Liver of Rats Receiving High-Fructose Ration

We studied the expression of genes encoding enzymes of carbohydrate and lipid metabolism ketohexokinase (Khk), glucokinase (Gck), pyruvate kinase (Pklr), acetyl-Co-carboxylase (Acaca), fatty acid synthase (Fasn), stearoyl-CoA desaturase (Scd), and their transcription regulators ChREBP (Mlxipl), SREBP-1c (Srebf1), and PPARα (Ppara) in rat liver. Control group rats received a semisynthetic ration over 20 weeks. Experimental group 1 received a semisynthetic ration and 20% fructose solution instead of drinking water. Experimental group 2 rats received a semisynthetic ration with quercetin (0.1% fodder weight) and 20% fructose solution. Consumption of 20% fructose solution (experimental group 1) led to an increase in Scd expression in comparison with the control and did not affect the expression of other genes. Addition of quercetin to the ration (experimental group 2) led to a decrease in the expression of Khk, Gck, Fasn, Scd, Mlxipl, and Ppara genes in comparison with experimental group 1. The results suggest that quercetin reduced the expression of genes of carbohydrate and lipid metabolism enzymes in the liver of rats receiving high-fructose ration.

[Effect of quercetin on the expression of the carbohydrate and lipid metabolism genes in the liver of rats with genetic]

Quercetin (Q; 3,3',4',5,7-pentahydroxyflavone) is considered as a promising component of specialized products for the correction of metabolic disorders in obesity and metabolic syndrome. At the same time, the results of evaluating the clinical efficacy of Q are ambiguous, and the mechanisms of its influence on lipid and carbohydrate-energy metabolism are not well understood. The aim of the work was to study the effect of quercetin (Q 3,3',4',5,7-pentahydroxyflavone) on the expression of key glycolysis and lipogenesis enzymes' genes in Zucker-Leprfa (Z) rats characterized by hereditary obesity, compared to «wild-type» Wistar (W) rats. Material and methods. 24 male Z rats and 32 male W rats aged 8-10 weeks were used. Animals of each line were divided into 4 groups of equal numbers. For 62 days the animals of the first groups (controls) received a balanced diet according to AIN93M, the seconds - the same diet with Q added in a dose of 50 mg/kg body weight. Animals of the third groups received a high-fat, high-carbohydrate diet (HFCD) with fat 30% by weight and with the replacement of drinking water with a 20% solution of fructose, the fourths groups - the same diet and supplementation with Q. After removing animals from the experiment, expression levels of liver carbohydrate and lipid metabolism genes Khk, Gck, Pklr, Acaca, Fasn, Scd, Srebf1, Mlxipl, Ppara and Pparg were determined by real-time polymerase chain reaction (RT-PCR) with reverse transcription using Actb and Gapdh as reference genes. The levels of triglycerides, total and HDL cholesterol, lipolytic activity and immunoreactive leptin were determined in plasma. Results and discussion. When comparing two animal lines, a significantly higher level of expression of Ppara, Pparg, Mlxipl, Acaca, Fasn, Scd was shown in Z rats compared to W rats, which is consistent with the development of dyslipidemia in the first ones and elevated levels of leptin under both types of diets used. The addition of Q caused in W rats a decrease in the expression of Scd, Mlxipl, Khk and Gck, more pronounced on the background of HFCD whereas in Z rats there were no similar effects, or they had the opposite direction. In addition, in Z rats, consumption of Q led to increased expression of Pklr, which was not observed in W rats. Conclusion. The modulating effect of Q on the expression of key genes of lipid and carbohydrate metabolism enzymes significantly differs in wild-type W rats and mutant Z rats with hereditary obesity, and this difference appears to be potentiated by the consumption of excess fat and fructose.

[Effects of quercetin on protective capacity in rats fed a high-fructose diet]

The purpose of the study was to determine effects of quercetin on protective capacity parameters in the experiment on rats fed a high fructose diet. Rats of the control group received a semi-synthetic (s/s) diet and water; animals from the 1st experimental group - s/s diet and 20% fructose solution instead of drinking water; rats of the 2nd experimental group- s/s diet with quercetin (0.1% indiet) and 20% fructose solution instead of drinking water for 20 weeks. Parameters of antioxidant status [total antioxidant activity (AOA), the content of malondialdehyde (MDA) and lipids hydroperoxides, the level of reduced and oxidized glutathione, activity of superoxide dismutase, catalase, glutathione peroxidase, paraoxonase-1, hemeoxygenase-1, NAD(P)H-quinone oxidoreductase], the activity of xenobiotic-metabolizing enzymes [CYP1A1, CYP1A2, CYP2B1, CYP3A, UDP-glucuronosyltransferase (UDP-GT) and glutathione transferase] were studied in plasma and liver of rats. Consumption of the high-fructose diet led to changes in some parameters: diminution of AOA in blood plasma, decrease of AOA and MDA level, unsedimentable activity of lysosomal enzymes, increase of the UDP-GT activity in liver. The inclusion of quercetin in the diet did not affect the studied parameters, except for a more pronounced decrease of the unsedimentable activity of lysosomal enzymes in rat liver. The results of the study indicated that there was no significant effect of quercetin on the protective capacity of rats at the initial stage of obesity caused by high-fructose diet.

Biochemical and Morphological Parameters of Inbred/Outbred Lines and DBCB Tetrahybrid Mouse in High-Sugar In Vivo Model of Metabolic Syndrome

Integral, biochemical, and morphological parameters and concentrations of vitamins, particularly lipid soluble vitamins, were analyzed in female mice of inbred DBA/2J line, outbred ICR-1 (CD-1) line, and DBCB tetrahybrid mice on the in vivo model of metabolic syndrome induced by consumption of 30% sucrose for 2 days. In contrast to inbred and outbred lines, DBCB tetrahybrid mice developed abdominal obesity, hypercholesterolemia, and pronounced morphological picture of fatty liver disease. The lipid-coupled transport of vitamin E to the liver is also enhanced in these animals, which compensated decreased supply of vitamin E to the liver under conditions of high-sugar ration. The observed interstrain differences can be related to genetic features of the used mouse lines and DBCB tetrahybrid mice and require further genomic, transcriptomic, proteomic, and morphological studies. The results of the study based on the in vivo model of metabolic syndrome allow identifying the key biomarkers for complex diagnostics and prognosis of metabolic syndrome complications, such as nonalcoholic steatosis of the liver.

[Effect of B-vitamin deficiency on biochemical, immunologic markers and trace element status of rats and mice of various lines]

Biochemical, vitamin, trace element and immunological changes were searched for the combined nutritional deficiency of vitamins B1, B2, B6 on in vivo models in rats and mice. Female rats of Wistar (W) strain and hybrids of the 1st generation of Dark Aguti and Wistar (DA x W) strains, female mice of BALB/c strain and DBCB tetrahybrids were used in experiment. Animals received for 35 days a balanced diet (control) according to AIN-93 or a similar diet with the exception of vitamins B1, B2, B6 (experimental groups). The content of vitamins B1, B2 in liver, riboflavin blood plasma level and urinary excretion of thiamine, riboflavin and 4-pyridoxic acid were determined, as well as in rats: blood and liver content of α-tocopherol and retinol, blood biochemical indices of lipid and nitrogen metabolism, activity of cytochrome P isoforms-450 (CYP) in liver; in mice: the circulating levels of pro- and anti-inflammatory cytokines of blood plasma, in animals of both species - the content of essential and toxic elements in the kidneys. DAxW rats compared to W and DBCB mice compared to BALB/c were more sensitive to the development of B-vitamin deficiency judging by the B-vitamin status indicators. In the rats of the experimental groups, there were signs of a deterioration in blood and liver levels of vitamin E, multidirectional shifts in vitamin A sufficiency, increased activity of the CYP3A isoform (6β-TG), a decrease in triglycerides, total protein and albumin fraction levels with an increase in urea level. Manifestation degree of these effects depended on the choice of the animal's line. In mice, the B-vitamin deficiency was characterized by an increase in the levels of proinflammatory cytokines TNF-α, IL-10, IL-Ιβ, IL-6 and a decrease in IFN-γ and IL-17A. The content of magnesium, copper, zinc, chromium and silver was lowered, of cesium - was increased in the kidneys of the rats of the experimental groups. In mice, B-vitamin deficiency resulted in diminishment of magnesium, copper, zinc, chromium, selenium, cadmium and lead content, excess accumulation of cobalt and cesium. Some of these biomarkers are supposed to be used in pre-clinical evaluation of the effectiveness of new vitamin complexes, specialized foods and dietary supplements, as well as studies of interactions of various vitamins.

Neuromotor Activity, Anxiety and Cognitive Function in the In Vivo Model of Alimentary Hyperlipidemia and Obesity

Behavioral indicators characterizing specific features of the pathological process of alimentary-dependent diseases were studied using in vivo model of alimentary hyperlipidemia in rats and mice. Rats and mice of the control groups received balanced semisynthetic diet for 63 days; animals of the experimental groups received a diet with high fat content (30% dry weight), balanced or high-fat diet with fructose solution instead of water, balanced cholesterol-enriched diet (0.5% dry weight), or balanced cholesterol-enriched diet with fructose solution. During the experiment, the mass of food, consumed by the animals, was monitored daily. Muscle tone was assessed by the front paw grip strength on days 33 and 54 of the experiment. Anxiety was tested in the elevated plus maze on days 36 and 57. Behavior and memory were assessed by conditioned passive avoidance reflex on days 39, 40, and 61. A significant increase in muscle tone was revealed on day 54 in rats fed with a balanced diet with fructose, and in mice, that received a similar diet, supplemented with fructose and cholesterol. Anxiety in the second test (day 57) was significantly decreased in rats fed high-fat diet and increased in mice fed high fat diet and high fat diet with fructose. In the second test, additional amount of cholesterol in the diet was the factor that significantly improved both short-term and long-term memory in both species. In mice, in contrast to rats, addition of fructose, including combination with high-fat diet, significantly worsened short-term and long-term memory. Thus, dietary factors, contributing to alimentary dyslipidemia development in rats and mice, can significantly affect the indices of neuromotor activity, anxiety level and cognitive functions, and the nature and direction of these changes are largely species-specific.

[The influence of separate and combined supplementation with curcumin and quercetin on the protective capacity in rats]

The purpose of the study was to determine the effects of curcumin (CUR) and quercetin (QUER) on the expression of genes and activity of prototypical Nrf2/ARE- and AhR/ XRE-regulated enzymes. Investigation was carried out on male Wistar rats with initial body weight (230-235 g b.w.) that received for 14 days CUR (200 mg/kg b.w.) and QUER (200 mg/kg b.w.) separately or in combination within the standard semi-synthetic diet. The expression of genes and activity of Nrf2/ARE - regulated enzymes - heme oxygenase- 1(HO-1), NAD(P)H:quinone oxidoreductase 1 (NQO1), AhR/XRE-regulated CYP1A1, CYP1A2 enzymes and the mRNA level of transcription factors Nrf2 and AhR were determined in rats liver. Also the expression of gene CYP3A1 and activity of CYP3A, UDP-glucuronosyltransferase, glutathione transferase were studied in rats liver. Along with this the total antioxidant activity (AOA), malondialdehyde and lipid hydroperoxides levels were determined in blood plasma and liver. The reduced and oxidized glutathione level, total and unsedimentable activity of lysosomal enzymes were investigated in rats' liver. QUER, especially in combination with CUR, increased the AOA of blood plasma and reduced the content of lipid hydroperoxides in it. CUR and QUER did not affect NQO1 activity, but the combined action caused an increase in the HO-1 activity without affecting the expression of the corresponding gene (Hmox1) and Nrf2 gene. CUR and, to a lesser extent QUER, had a strong inducing effect on CYP1A1, CYP1A2, CYP3A activity, but only the CYP1A1 activation was accompanied by the induction of CYP1A1 gene. The inducing effect of CUR and QUER on the activity of CYP450 enzymes greatly enhanced by their combined action. Membrane stabilizing action of CUR and QUER was also strongly expressed under its combined intake. Thus, we can conclude that CUR and QUER, especially in combination, contribute to the protective and adaptive capacity.

[Comparative evaluation of vitamin status and biochemical markers of metabolic syndrome on the models of rodents receiving rations with high quotas of different sugars]

Metabolic syndrome (MS) is one of the leading causes of non-infectious pathology among the population of developed countries. It is necessary to have experimental in vivo models of MS for pre-clinical testing of new approaches to its dietary therapy. The purpose of the study was a comparative analysis of functional, biochemical and vitamin markers that characterize the effect of diets with different composition of simple carbohydrates (sugars) on female Wistar rats and female C57Black/6J mice. Animals of each species (n=80) were divided into 5 groups of equal numbers. The animals of the 1st (control) group received a balanced semi-synthetic diet, and the animals of groups from the 2nd to the 5th - the same diet and 30% solutions of sugars - glucose (Gl), fructose (Fr), equimolar mixture Gl and Fr and sucrose instead of water, in the regime of free access for up to 133 days. Measured values included blood pressure, mass of internals, biochemical parameters of blood plasma, the activity of CYP1A1, CYP1A2, CYP2B1, CYP3A and glutathione transferase (GT) in liver, glutathione peroxidase (GP) in erythrocytes, the content of vitamins A and E in blood plasma and in liver, the level of vitamins B₁ and B₂ and nicotinamide coenzymes in liver. Interspecific differences in the response to sugars manifested in a decrease in the solid diet consumption in mice (in contrast to rats), so that the total consumed energy value in experimental groups of mice did not differ systematically from control, and the weight gain was reduced. Liver was the most sensitive organ to addition of sugars in both rats and mice with mass significantly increasing by the 2nd and the 4th months of the experiment. Hyperglycemia and triglyceridemia were the most noticeable in rats receiving Fr. The concentration of phosphorus increased significantly in blood plasma of all rats groups that received sugars. In rats there was a decrease in the activity of CYP1A1 and CYP1A2 in groups 3 and 5, the activity of CYP2B1 in groups 2 and 5, the increase in HT activity in groups 2, 4 and 5, and GP in group 3 at 56th day of experiment. There was a significant decrease in this index in group 3 at the 56th and the 133rd days of the experiment, and in groups 4 and 5 - at the 56th day. Plasma tocopherol to triglycerides ratio decreased in rats of group 3 at the 56th and 133rd days, groups 4 и 5 - at 56th day, which indicated the decrease of vitamin E safety. Sugars consumption suppressed retinol palmitate accumulation in the liver of rats and mice, and alpha-tocopherol in mice. It was concluded that Fr had the greatest effect on the studied indicators of the organism, and the rats showed the most significant similarity with the clinical picture of MS.

[Effect of rutin and hesperidin on the expression of Nrf2 gene and the activity of hemoxygenase-1 and NAD(P)H-quinone oxidoreductase at their separate and combined action]

Flavonoids rutin (R) and hesperidin (Hes) have a broad spectrum of the biological activity based on their antiradical properties and ability to increase the activity of antioxidant enzymes, including the activity of heme oxygenase-1 (HO-1) and NAD(P)H-quinone oxidoreductase (QR). It is supposed that the main regulator of the activity of HO-1 and QR is the transcription factor Nrf2. The purpose of the study was to determine the effects of R and Hes on the expression of Nrf2 gene and protein, on the activity and mRNA and protein expression of HO-1 and QR at their separate and combined action. Administration in diet of male Wistar rats (with initial body weight 180-200 g) R (400 mg/kg b.w.) and Hes (400 mg/ kg b.w.) during 14 days separately or in combination had no toxic or pro-oxidant effect, which were assessed by the level of liver MDA, hydroperoxides of lipids, reduced and oxidized glutathione. R and, to a lesser extent, Hes caused increased activity of HO-1 and QR. Their combined effect on the activity of HO-1 did not differ from the separate effect of each flavonoid. The combined action of R and Hes on the activity of QR was additive. According to Western blotting, changes in HO-1, Nrf2 and QR protein levels under the action of R and Hes separately or in combination were not statistically significant. The results of real time PCR demonstrated the presence of small, but statistically significant, changes in the level of expression of the genes Nrf2 (Nrf2), HO-1 (Hmox1) and QR (NQO1) both for separate and combined action of R and Hes. Thus, the obtained results showed that high-dose of R and Hes separately and in combination didn't significantly affect the gene and protein expression of transcription factor Nrf2 and that the increased activity of HO-1 and QR was not associated with the increased expression of Hmox1 and NQO1 genes.

[The effect of rutin and hesperidin on the expression of Nrf2- and AhR-regulated genes and CYP3A1 gene in rats intoxicated with carbon tetrachloride]

The purpose of the study was to determine the effects of rutin (R) and hesperidin (Hes), the main representatives of two most studied subclasses of flavonoids - flavonols and flavanones, on the expression of prototypical Nrf2 and AhR-regulated genes and CYP3A1 gene in rats intoxicated with carbon tetrachloride (CCl4). Investigations were carried out on 5 groups of male Wistar rats with the initial body weight (b.w.) 180-200 g (n=40). Rats of the control group and the 1st experimental group received for 14 days the semisynthetic diet, rats of the 2nd experimental group - the same diet plus R (400 mg/kg b.w.), the animals of the 3rd experimental group received the diet with Hes in the same amount, of the 4th experimental group - diet with R (400 mg/kg b.w.) and Hes (400 mg/kg b.w.). Animals of the experimental groups 24 hours before the end of experiment were injected intraperitoneally CCl4 at a dose of 0.5 ml/kg b.w. in olive oil; rats of the control group were injected equal amount of olive oil. For gene expression assessment the mRNA content of NAD(P)H-quinone oxidoreductase (NQO1), heme oxygenase-1 (Hmox1), Nrf2 (Nrf2), AhR (AhR), CYP1A1, CYP1A2, CYP3A1 and β-actin (Actb) in rat liver was determined by real-time RT-PCR. The results showed that in rats intoxicated with CCl4, enrichment of the diet with R, but not with Hes, led to a significant increase in the expression of genes Hmox1, NQO1 and CYP3A1. Combined intake of R and Hes with the diet led to additivity of their action on the expression of Hmox1 gene and to synergism in the effect on the expression of genes NQO1 and CYP3A1. A moderate increase in the levels of expression of AhR and CYP1A2 genes as compared to their expression in rats treated with CCl4 only, CCl4 and R or CCl4 and Hes has been noted. Thus, for the first time on the model of oxidative stress in rats the data have been obtained showing at the gene expression level a synergism of action of two flavonoids - R and Hes, widely present in the daily human diet.

[Comparative characteristics of in vivo models of hyperlipidemia in Wistar rats and C57Bl/6 mice]

In vivo simulation of lipid disorders (hyperlipidemia, obesity, metabolic syndrome, atherosclerosis) is of considerable interest to search for genomic, transcriptomic and metabolomic markers that allow for differential diagnosis, prognosis and selection of personalized diet therapy in patients with such pathology. The aim of the study was the development and characterization of basic biochemical parameters of in vivo models of alimentary hyperlipidemia in outbred rats and inbred mice. The experiment was con­ducted on 48 growing female Wistar rats, and 48 growing female mice of line C57Black/6, which were divided into 12 groups of 8 animals per group. Within 63 days the rats and mice of first (control) group received a balanced semi synthetic diet (BD), the animals of the second groups - high-fat diet (HFD) with 30% of the total fat by weight of dry feed, third groups - BD and fructose solution (Fr) instead of water, the fourth groups -HFD + Fr, fifth groups - BD supplemented with 0.5% cholesterol (Cho) by weight of dry feed, sixth groups - BD with Cho and Fr. The amount and composition of diets consumed were corrected during the experiment for their closest approach in calories. After removal of animals from the experiment there were determined the mass of internal organs, HDL, LDL, total cholesterol, triglycerides, glucose in blood plasma, total lipids and their fatty acid composition in liver, ghrelin, GIP, GLP-1, glucagon, leptin, PAI-1, resistin levels in blood plasma. It was found that in both species the liver is the most sensitive to nutritional imbalance, nutrient exerting the greatest impact on this was Fr. In rats, as compared to mice, there was significantly more pronounced shifts in lipoprotein spectrum in response to nutritional imbalances, especially to the consumption of additional Cho, which was manifested in an increase of LDL, decrease of HDL and magnification of atherogenic index. In the liver of rats fed diets with Cho, marked steatosis developed manifested in a disproportionate increase in the lipid content and accompanied by changes in their fatty acid composition, especially in the ratio ω6 to ω3 PUFAs. Changing of hormones - regula­tors of carbohydrate metabolism (GLP, glucagon) and ghrelin was significantly greater in mice than in rats as a result of consumption of additional Fr. Effect had the opposite direction in two species of Cho and Fr combining on leptin levels. The significance is dis­cussed of the revealed interspecies differences in the light of the characteristics of lipid and glucose metabolism in these two lines of animals that are the most common models of alimentary-dependent diseases.

[Changes in proteome profiles of rat liver microsomes induced by silicon dioxide nanoparticles]

The effect of daily intragastric administration of an aqueous dispersion of silicon nanoparticles (NPs) (the dose range from 1.0 mg/kg to 100 mg/kg body weight for 28 days) to rats on the proteomic profile of liver microsomes has been investigated by 2D-electrophoresis followed by subsequent mass spectrometry identification. The liver microsomal fraction was isolated by differential centrifugation and its protein composition was analyzed by 2D-polyacrylamide gel electrophoresis. Identification of protein spots was carried out using MALDI-TOF mass spectrometric analysis. The mass spectrometry analysis revealed the protein GRP78 (78 kD glucose-regulated protein precursor), belonging to the family of heat shock proteins. This protein present in animals of the control group was not detected in NP-treated rats of group 2 (1 mg/kg body weight/day) and group 3 (10 mg/kg body weight/day). This protein predominantly localized in the liver cell endoplasmic reticulum and plasma membrane has the chaperone biological activity. Possible mechanisms of the effects of engineered nanoparticles on biosynthetic processes in the body are discussed.

[Effects of rutin on protective capacity in rats]

The purpose of the study was to determine effects of rutin dietary administration on the activity of xenobiotic-metabolizing enzymes and antioxidant status. The study has been carried out on 3 groups of male Wistar rats (n = 8 in each), with initial body weight 100-120 g. Animals of the control group (1st group) received standard semi-synthetic diet, the experimental groups--the same diet with rutin in the amount of 40 mg/kg b.w. (2nd group) or 400 mg/kg b.w. (3rd group). The duration of the experiment was 2 weeks. In rat liver the activity of quinone reductase (QR), heme oxygenase-1 (HO-1), paraoxonase-1 (PON-1), glutathione-S-transferase (GST), ethoxyresorufin-O-dealkylase (EROD) activity of CYP1A1, methoxyresorufin-O-dealkylase (MROD) activity of CYP1A2, tes- tosterone 6β-hydroxylase (6β-TG) activity of CYP3A, total antioxidant activity (AOA) and malondialdehyde (MDA) content have been investigated. The expression of genes CYP1A1, CYP1A2 and CYP3A has been measured by reverse transcription-polymerase chain reaction (RT-PCR). The stability of lysosome membranes was estimated by the change of unsedimentable activity of lysosomal enzymes--arylsulfatase, β-galactosidase and β-glucuronidase. Rutin administration led to dose-dependent increase in the activity of antioxidant enzymes. In rats of the 3rd group received high-rutin diet the activity of QR, HO-1, PON-1 and GST increased by 68, 29, 17 and 22%, respectively, compared to the control (1st group); MDA level and AOA have not changed. Activity of EROD and MROD in liver microsomes of rats treated with rutin at a dose of 40 mg/kg b.w. (2nd group) increased by 33 and 58%, respectively, with a moderate increase in mRNA level of CYP1A1 and CYP1A2. Increasing the dose of rutin up to 400 mg/kg b.w. (3rd group) resulted in the decrease of the degree of EROD and MROD activation by 18 and 15%, respectively, compared to the 2nd group. Rutin had no significant effect on the activity of 6β-TG and on the expression of CYP3A1 gene. Rutin dietary administration led to dose-dependent reduction of the unsedimentable activity of lysosomal enzymes, indicating the strengthening of the stability of lysosomal membranes. Thus, the obtained results showed that in healthy, intact rats high doses of rutin in the diet moderately but statistically significantly activate enzyme systems responsible for the protective and adaptive capacity of the organism.

Effect of polyunsaturated fatty acids ω-3 on the induction of activity and expression of CYP1A1 and CYP1A2 genes in the liver of rats under the influence of indole-3-carbinol

Supplementation of the ration with eicosapentaenoic and docosahexaenoic ω-3 polyunsaturated fatty acids (PUFA) in doses of 0.3 and 1 g/kg body weight for 4 weeks had no effect on ethoxyresorufin O-dealkylase (EROD) activity and expression of the CYP1A1 gene in male Wistar rats, but caused a dose-dependent increase in methoxyresorufin O-dealkylase (MROD) activity of CYP1A2 (by 28 and 73%, respectively) without significant changes in CYP1A2 mRNA expression. ω-3 PUFA had no effect on the indole-3-carbinol-induced (20 mg/kg body weight over the last 7 days of the experiment) EROD activity and expression of CYP1A1 mRNA. The indole-3-carbinol-induced MROD activity was shown to increase by 6.2 times in rats not receiving ω-3 PUFA and only by 3.9 and 2.7 times in animals receiving ω-3 PUFA. The indole-3-carbinol-induced expression of CYP1A2 mRNA slightly increased in animals receiving ω-3 PUFA. Our results suggest that the effect of ω-3 PUFA on the induced and basal activity of CYP1A2 is not related to modulation of CYP1A2 gene expression.

[Effects of rutin on the activity of antioxidant enzymes and xenobiotic-metabolizing enzymes in liver of rats fed diets with different level of fat]

The study has been carried out on 6 groups of male Wistar rats, which received semi-synthetic diets within 28 days. Rats of 1st and 4th group received fat-free diet, 2nid.and 5th - diet containing standard amount of fat (10% by weight, 26% by caloric content; lard/sunflower oil - 1/1); 3rd and 6th group - a high-fat diet (30% by weight, 56% by caloric content). During the last 14 days of the experiment rats received rutin in the dose of 40 mg/kg b.w. AOA, MDA level and the activity of paraoxonase I have been evaluated in blood serum. In rat liver along with the parameters of the antioxidant status (MDA level, activity of paraoxonase 1, quinone reductase, heme oxygenase-1) the activity of xenobiotic-metabolizing enzymes (XME) (CYP1A1, CYP1A2, CYP3A1, CYP2B1, UDP-glucuronosyl transferase and glutathione transferase) and the activity of lysosomal enzymes (arylsulfatase A and B, β-galactosidase and β-glucuronidase) have been investigated. Elevation of the activity of antioxidant enzymes and XME in liver with the increase of diet fat content has been-noted. Rutin admihistration had no effect onparamete6rs of antioxidant status and decreased unsedimentable activity of lysosomal enzymes that did not depend on fat content in the diet. Rutin receiving increased the activity of all studied XME in rats fed standard diet, but practically did not effect on their activity in rats fed by fat-free and high-fat diets. Thus, rutin in pharmacological dose has no effect on the activity of antioxidant enzymes that doesn't depend on the level of fat in the diet, while the decrease or increase of diet fat content modulates (weakens) the influence of rutin on the XME activity.

[Effects of vitamins deficiency on the cytochrome P450 inducibility in rats]

The purpose of the study was to determine multi-vitamin deficiency effects on the inducibility of main isoforms of cytochrome P450 in the rat liver. The study was carried out on 4 groups of Wistar rats. Rats of the 1st and 3rd group received semi-synthetic diets containing adequate (100% of recommended vitamin level) level of vitamins, the 2nd and 4th--the semi-synthetic diet containing vitamins in the amount of 20% from adequate level. The duration of the experiment was 4 weeks. During the last week indole-3-carbinol (I-3-C) in dose of 20 mg/kg body weight was added to the diet of the 3rd and 4th group of rats. Vitamin E content in liver and blood serum declined by 59 and 34%, respectively in rats which were fed vitamin-deficient diet (2nd group); vitamin A level decreased by 5 times in the liver, but was not changed in blood serum. Multi-vitamin deficiency in the diet led to the increase in the liver ethoxyresorufin O-dealkylase (EROD) activity of CYP1A1, methoxyresorufin O-dealkylase (MROD) activity of CYP1A2 and testosteron 6beta-hydroxylase (6beta-TG) activity of CYP3A by 11, 80 and 53%, respectively, and gene expression of CYP1A1, CYP1A2, CYP3A and AhR by 8,5; 1,6; 2,4 and 3,6 fold. In rats fed diet with adequate levels of vitamins (3rd group) I-3-C increased activity of EROD and MROD by 4,4 and 5,5 fold, and the expression of CYP1A1, CYP1A2 and AhR genes by 148; 3 and 3,5 fold compared to the parameters of the 1st group (without I-3-C). Multi-vitamin deficiency increased I-3-C-related induction of EROD activity and expression of CYP1A1 and CYP1A2 genes, but decreased I-3-C-related induction of the MROD activity. Thus, 5-fold reducing of vitamin content in rat diet lead to significant changes in activity and inducibility of cytochrome P450 of CYP1A and 3A family, which play a key role in the detoxification and metabolism of drugs.

[Effects of omega-3 polyunsaturated fatty acids on antioxidant capacity in rats]

Dietary administration of omega-3 polyunsaturated fatty acids (EPA + DHA, 1,2:1) at dose 0.3 or 1 g/kg bw during 4 weeks led to minor (by 14% and 17%, p<0.05) decrease of serum antioxidant capacity and serum level of vitamin E (by 30% and 31%, p<0.05) and the activity of paraoxonase-1 (by 14% at 0.3 g/kg bw, p<0.05). The activity of antioxidant enzymes in liver increased in a dose-dependent manner. At higher dose of omega-3 polyunsaturated fatty acids a 45% increase in the activity of paraoxonase-1 (p<0.05), 21% -heme oxygenase-1 (p>0.05), 68% - quinone reductase (p<0.05), 19% - glutathione S-transferase (p<0.05) compared to the control group was found. The direct relationship between activities of enzymes and increase of MDA level in liver (by 47 and 107%, p<O.05) was found. Selected doses of omega-3 polyunsaturatedfatty acids had no significant effects on total liver antioxidant capacity, microsomes NADPH-Fe2+-induced lipid peroxidation and lysosomal membranes stability.

[Studies of effects of aluminum oxide nanoparticles after intragastric administration]

Growing Wistar rats received intragastrically nanoparticles (NPs) of aluminum oxide (Al2O3) daily during 28 days at doses of 1 or 100 mg per kg body mass. There were studied body mass of animals, relative mass of internals, rate of protein macromolecules absorption in the gut, oxidative damage of DNA, pool of tissue thiols, activity of hepatic enzymes of xenobiotic detoxication system, biochemical and hematological blood indices, stability of lysosome membranes, condition of antioxidant defense system, apoptosis of hepatocytes. Conducted experiments didn't reveal any marked toxic action of Al2O3 NPs on rats after 28 days of administration both in high and low dose. Among effects probably related to NPs influence on animals there were lowering of relative liver and lung masses, decrease of hepatic thiol pool, activity of CYP1A1 isoform in liver and glutathione reductase in erythrocytes, increase of diene conjugates of fatty acids in blood plasma. Said shifts were small in magnitude, didn't come out of margins of physiological norm and didn't show any distinct relation to NPs dose. However considering great importance of this nanomaterial as probable environmental contaminant the studies of it's toxicity must be continued in conditions of low doses (less than 1 mg per kg body mass) for long period of time.

[Effects of dietary fat level on the xenobiotic metabolism enzymes activity and antioxidant enzymes in rats]

Male Wistar rats received fat-free diet or diets containing 5, 10 and 30% of fat (sunflower oil + lard, 1:1) for 4 weeks. The direct relationship between dietary fat level and ethoxyresorufin O-dealkylase activity of CYP1A1, methoxyresorufin O-dealkylase activity of CYP1A2, pentoxyresorufin O-dealkylase activity of CYP2B1 and testosterone 6beta-hydroxylase activity of CYP3A was found. Activities of key enzymes of phase II xenobiotic metabolism (total activity of glutathione transferase, activity of UDP-glucuronosyle transferase) and antioxidant enzymes (catalase, glutathione peroxidase, glutathione reductase, paraoxonase-1 and heme oxygenase-1) also increased with higher dietary fat level.

[Effects of polyvitamin deficiency on the activity of xenobiotic-metabolizing enzymes in rat liver]

The activity of xenobiotic-metabolizing enzymes was studied in the liver of male Wistar rats, which were fed for 4 weeks diets, containing 100 (control), 50 and 20% of vitamin adequate level. Moderate (50%) polyvitamin deficiency increased activity of EROD (by 13%), MROD (by 34%; p<0,05), 4-nitrophenol hydroxylase (by 16%), 6beta-testosterone hydroxylase (by 17%), UDP-glucuronosyle transferase (by 26%, p<0,05) and quinone reductase (by 55%, p<0,05). Deep (20%) polyvitamin deficiency decreased in liver activity of MROD (to 78% of control level, p<0,05), 4-nitrophenol hydroxylase (to 74%, p<0,05), heme oxygenase-1 (to 83%, p<0,05) and quinone reductase (to 60%, p<0,05). At the same time a 22% increase in the UDP-glucuronosyle transferase activity compared to the control group was found; activities of EROD, PROD, 6beta-testosterone hydroxylase and the total activity of glutathione S-transferase were unchanged. Deep polyvitamin deficiency had no significant effect on CYP1A1 mRNA and AhR mRNA level, whereas the expression of CYP1A2 mRNA and CYP3A1 mRNA were decreased to 62 and 79%, respectively, as compared with control.

[Effect of dietary fat on vitamin status of rats]

The influence of low (1%) and high (31%) diet fat content (sunflower-seed oil and lard 1:1 at a ratio of 1:1) on vitamin A, E, B1 and B2 status of growing Wistar rats (8 rats per group) with initial body weight 80-100 g has been investigated. The semi-synthetic diet contained vitamin mixture in doses covering the physiological requirement of these animals. The increase of fat content (31%) in the diet due to the presence of vitamin E in sunflower-seed oil automatically lead to 1,7-fold increase consumption of this vitamin compared to the control group. Diet fat content did not affect the level of vitamins B1 and B2 in rat liver. Excessive intake of fat and vitamin E for 6 weeks did not influence on the content of blood plasma vitamin E and rat liver vitamin A occurs at the same time, while significant 1,9 fold elevation of liver vitamin E level and 26 per cent increase of blood plasma vitamin A concentration. The almost complete exclusion of fat from the diet had no effect on blood plasma level of alpha-tocopherol and retinol, but resulted in a significant decrease of vitamins A and E content in rat liver by 40 per cent, indicating a deterioration of sufficiency with these fat-soluble vitamins. The analysis of the results obtained in this investigation and literature data have suggested that under excessive as well as under decreased consumption of fat there is a risk of the development of polyhypovitaminosis. Vitamin complex supplementation is required to prevent a possible worsening of vitamin status under diets with modified fatty component.

Effects of combined treatment with resveratrol and indole-3-carbinol

Male Wistar rats received a semisynthetic diet with resveratrol (100 mg/kg), indole-3-carbinol (20 mg/kg), or a mixture of these compounds in the same doses for 1 week. Activities of ethoxyresorufin dealkylase (EROD), methoxyresorufin dealkylase (MROD), pentoxyresorufin dealkylase (PROD), and 6β-testosterone hydroxylase (6β-TH) and the content of mRNA for CYP1A1, CYP1A2, and CYP3A1 were elevated in the liver of rats receiving indole-3-carbinol. These changes were accompanied by an increase in activity of phase II xenobiotic metabolism enzymes (quinone reductase, hemoxygenase-1, glutathione transferase, and UDP glucuronosyl transferase). Resveratrol did not modify activity of these enzymes. After combined treatment with the test compounds, resveratrol suppressed the indole-3-carbinol-induced increase in activities of EROD, MROD, PROD, and 6β-TH, and expression of the corresponding genes. Combined treatment was characterized by potentiation of the antioxidant effects of these compounds.

[Effects of green tea extract and its components on antioxidant status and activities of xenobiotic metabolizing enzymes of rats]

Dietary administration of green tea extract (GTE) or epigallocatechin gallate (EGCG), quercetin (Qu) or caffeine (Cf) in doses equal to their concentration in GTE led to an increase of serum and liver antioxidant capacity and strengthening stability of microsomal and lysosomal membranes in rats. The antioxidant efficiency of EGCG and Qu was considerably higher than that of GTE. There were significant differences in the effects of EGCG, Qu and GTE on the activities and expression of mRNA for CYP1A1, CYP1A2 and CYP3A1. But feeding both GTE and Cf to rats results in similar elevated activities of CYP1A1, CYP1A2, UDP-glucuronosyl transferase and glutathion transferase. Our results suggest that Cf is the main contributor to GTE effects on activities of xenobiotic metabolizing enzymes.

[Evaluation of antioxidant and hepatoprotective properties of strain Lactobacillus casei 114001 in carbon tetrachloride-induced liver toxicity model]

Daily oral administration to rats of probiotic strain Lactobacillus casei 114001 (L.c.) at dose 2,8 x 10(10) cfu/rat during 8 days reduced oxidative stress and liver lesions, induced by a single intraperitoneal administration of carbon tetrachloride (CCl4) at dose 0.5 ml/kg b.w. It was evidenced by several histopathological and biochemical markers, characteristic for CCl4 toroxicity. Membrane damage by toxin was reduced in rats, treated with L.c.: alanine aminotransferase activity in plasma and nonsedimentable activity of lysosomal enzymes in liver were significantly decreased. Treatment with L.c. resulted in partial recovery of activities of antioxidant enzymes and enzymes of xenobiotic metabolism and full recovery of antioxidant capacity of liver cytosol. High level of activity and expression of proteins heme oxygenase and Nrf2 were maintained.

[Regularities of formation in a general population of serum antibodies to previously circulated influenza A viruses]

The spectrum of antibody production against hemagglutinin of all known influenza A virus serotypes after influenza A (H3N2) infection in persons of all age groups (from 1 month to 72 years) was analysed to investigated the regularities of accumulation of antibodies against influenza A viruses gone out of circulation. For the same purpose, a long-term (many years) longitudinal analysis of serum anti-HA antibody levels against "old" influenza A (HSW1N1), A (H0N1), A (H1N1), A (H2N2), and A (H3N2) viruses was carried out in children and adults of various age groups in 6 cities of different geographical regions of the country. Based on the results of the study, the concept of the "original antigenic sin" is analysed critically, and a new original concept on the regularities of antibody genesis against previously prevalent influenza A viruses and the factors affecting this process has been formulated.

[Indicators of collective immunity to influenza depending on the blood group and sex of the population]

Immunological investigations of the time course of serum anti-HA and anti-NA antibodies against influenza A and B viruses in the female and male population with blood groups 0(I), A(II), B(III), and AB(IV) were carried out for several months. The persons with the blood group AB (IV) were shown to be most sensitive to influenza A and B. They were affected by the epidemic virus earlier and more severely than those with the other blood groups. A special method is proposed for prediction of the etiology of the forthcoming epidemic. A correlation between blood groups and titres of anti-HA but not anti-NA antibodies was observed. The view on the lack of the genetic factor influence on the affliction with influenza and antibody response in persons of different sexes is substantiated.